1. Field of the Invention
This invention relates to a system for improving the aerodynamic profile of vehicles by utilizing side vehicle fairing structures, especially for use on an intermodal chassis used to transport intermodal shipping containers by road (“Chassis” or “Chasses”). Additionally, the system can be employed on any trailer used in a tractor-trailer combined vehicle (“Truck”). The system improves fuel consumption without having a material adverse impact on operation or service procedures pertinent to the Truck.
2. Description of Related Art
The amount of power needed to move a vehicle over land or through the air increases with the speed of the vehicle due to aerodynamic drag. The amount of power necessary to overcome aerodynamic drag directly translates into increased fuel consumption, and thus increased emission of greenhouse gases and pollutants, and increased cost of operation.
A variety of innovations aimed at reducing the aerodynamic drag of various transport vehicles, including tractor-trailer combinations, have been introduced in the prior art. These include efforts to make the hood, windscreen, fenders, etc. more streamlined in form, as well as by adding fairings to the cab roof, and in some cases, to the trailer when the trailer is a “box” van or refrigerated heavy duty truck trailers. Hereinafter standard van and refrigerated “box” heavy duty truck trailers shall be referred to as “Van Trailer(s)”.
U.S. Pat. No. 6,799,791 discloses a vehicle fairing structure that can be deployed on the rear of a Van Trailer box to reduce drag at the rear end of the Van Trailer box. Since a significant amount of drag is also associated with the front of the Van Trailer box, where there is known to be an area of high pressure and relatively stagnant air approximately at the middle of the forward vertical face of the trailer cab, a front fairing structure for reducing this drag is disclosed in U.S. Pat. No. 7,604,284.
It is also the case that significant drag results from air entering under the Van Trailer, between the box and the road surface. A system that includes side fairings to reduce drag such is disclosed in U.S. Pat. No. 7,404,592. The foregoing patent and applications (The disclosures of U.S. Pat. Nos. 6,799,791, 7,604,284 and 7,404,592 are incorporated herein by reference.
While the foregoing side fairing systems are suitable for Van Trailer boxes, a significant amount of freight is moved using intermodal systems. In such systems, the trailer box is a separate component from the trailer chassis, so that multiple boxes (referred to as containers) can be stacked on container ships or flatbed railcars and single containers can be mounted on trailers for transit by Truck. When the containers are moved between their originating/final destinations by road or Truck, Chasses specially designed to accommodate the container are utilized. A crane or a forklift is typically used to lift a container on to and off of the Chassis.
Utilizing a side fairing in an intermodal application to reduce aerodynamic drag is challenging, because the design needs to take into account the foregoing modes of operation. To permit easier movement and stacking of containers, it may be desirable to secure the side fairing to the Chassis rather than the container. However, any side fairing design must take into consideration that the container may be lowered onto the Chassis in a tilted or otherwise imperfect orientation, thereby striking the fairing.
Intermodal containers are typically made of steel and are of robust, heavy construction so that they can withstand the rigors of being moved multiple times while securely protecting and supporting the freight that they carry. As a consequence, there is risk of damage to any side fairing mounted on the Chassis should the container be lowered onto the Chassis in any imperfect orientation. Perfect lifting/lower and perfect alignment of the container to the Chassis cannot always be achieved.